The ousted Trump administration member also unloads on Ivanka's "stupid" husband, Jared Kushner.
The former White House employee, who is still promoting her tell-all book "Unhinged," called the couple "White House Ken and Barbie" and answered her host's curiosity if the president is "really hot" for his daughter.
"I mean, he said it himself," Omarosa said. "I'm just going to say his own words, he wanted to sleep with his daughter."
"It's pretty disgusting," she continued. "He would pat her on the behind, he'd kiss her on the lips, he would rub her for very long periods of time. It was awkward."
Maher was shocked with Omarosa's candor, but further pressed and asked if Trump would act like that "in front of people."
"Yeah, absolutely," Omarosa replied. "She just loved it. She loved being daddy's little girl."
The "Celebrity Apprentice" star added that Ivanka seemed to have created a new accent over the years, because she used to have a "potty mouth, but maybe "cleaned it up for the White House."
Omarosa didn't have great things to say about Kushner either, who Maher joked "doesn't speak."
"[Kushner] is the one I'd be most curious to have dinner with," Maher said. "Because he might be smart?"
"He's that guy in the room who thinks he's the smartest guy in the room, who has absolutely no idea about what's going on," Omarosa told Maher in response. "He didn't even know basic political jargon. And when you try to correct him, he gives you that posture like, 'You, a woman of color, really trying to tell me something?'"
"The sad thing about Jared is that he doesn't know how stupid he sounds when he's talking about those things," she added.
Got a story or a tip for us? Email TooFab editors at email@example.com.